Pipe coupling



SePt- 2, 1941- R. J. FlsHER\ 2,254,997

PIPE COUPLING Filed Nov. 2, 1959 Patented Sept. 2, 1941 azteca:

PIPE coUPLING Reginald John Fisher, London, England, assignor to AveryEquipment Limited, London, England,

a British company Application November 2, 1939, Serial No. 302,586 InGreat Britain December 10, 1938 7Claiml.

'I'his invention relates to pipe couplings for connecting the ends ofsections ci piping, or for connecting a section of piping to areservoir, cylinder or other unit. Couplings tor this purpose have beenproposed in which a valve provided in each part of the coupling closesautomatically when the parts of the coupling are separated, and isopened by the connection of the coupling parts, 'so that iluid cannotescapefrom the ends oi' the pipes when the coupling parts are separated,but can flow freely through the coupling when the parts are connected,the valve in one coupling part being centrally disposed to engage anannular seating, and the valve in the other part being formed by anannularmember co-operating with a central fixed seating, and each valvebeing engaged by the seating member of the other when the coupling isconnected, and thereby unseated to open a passage through the coupling.'Ihe coupling, according to the present invention, is of the kind abovedescribed, which is mentioned hereafter as the type referred to.

The object of the invention is to provide a cou; pling which can beseparated or connected whilst a pressure substantially above atmosphericpres-4 sure exists in either `or both parts of the coupling without anyleakage taking place during the separating or connecting operations, andin which a substantially smooth and uninterrupted passage ior the iluidis provided through the coupling.

According to the invention, a pipe coupling of the kind referred to ischaracterised by the feature that the annular valve member is outsidethe fluid passage through the coupling, and has its rear face exposed atall times to the pressure in the coupling. i

The pipe coupling may have the central valve seat formed on the end of ahollow stem forming oi the coupling being slightly separated.

the fluid passage through that part of the coul pling, the annular valvemember sliding on the exterior of the said stem, and the annular valveThe coupling part shown in Figure 1 comprises a sleeve I0 having athread il formed on one end for the attachment of a pipe union, and atvthe other end an inserted annular seating member l2 held in place byturning inwards the edge I3 ofthe sleeve i0, the seating member having aconical face Il to form a seat for a valve member i5 slidable within thesleeve I0 and urged towards the seating face I4 by a spring I6. Thevalve member i6 has a head Il of less diameter than the interior of thesleeve I0, and a body portion i8 which is a sliding fit in the sleeve,the body being cut away at 2l for the passage of iluid. A

The other coupling part shown in Figure 2 also comprises a sleeve-likebody 22 having a thread 23 to receive a pipe union, and an inner annularprojection 24 forming an inner sleeve concentric with the main sleeve.Acentral hollow stem 25 formed at its end with a mushroom head 26extends from the inner sleeve 24 through the outerY sleeve, the stembeing secured in the inner sleeve by a shoulder 21 formed on the stem 25and expanded outwardly into a groove in the body 22. In the mainsleeve-like body 22 is slidably mounted an annular valve member 28having a truste-conical surface 3| to eng'age with the partsphericalseating 32 on the mushroom head 26 of the stem 25. Y A

The annular valve member 28 isa sliding tlt on the stem 25 at its endadjacent the surface 3|, but is internally stepped to provide anenlargement towards its other end thus forming a space 33 to receive aspring 34 tending to hold the valve member 28 up against its seat 32.The enlarged end of the valve member 28 is large enough to pass over theinner sleeve 24 of the body, which latter isprovided at its end with atruste-conical face 35 against which an annular packing member 36 ofrectangular cross section and made of rubber, soft metal or otherpacking material is urged. by a loose ring 3l which again has afrusta-conical face bearing on the packing 30, and is acted on at itsother side by the valve spring 88 to thrust it against the packing. Theconical faces of the sleeve 28 and ring 81 tend to thrust the packingoutwardly against the interior wall of the annular valve member 28. lowstem 28 has one or more apertures 88 just behind the mushroom head 28,which connect with the passage through the stem. The annular valvemember 28 is reduced in diameter exterior-ly at its outer end to a thehead 28. thus forming an external shoulder 8I which is recessed toreceive a packing ring 82 upon which the coupling part I8 engages whenthe two parts are concerned. The coupling part 22 is screw threadedexternally at 88, and the coupling part I8 is formed with an externalcollar 88 to be engaged by a winged cap nut 88 which may be screwed onto the thread 88 of the coupling part 22 to connect the two together. n

When the coupling parts I8 and 22 are bro t together, the reducedportion of the valve member 28 passes through the seating member I2onthe coupling part I8, and the en oi' the latter engages the packingring 82 on t e shoulder The holdiameter equal to that of 8I of the saidvalve member, the head 28 on the hollow stem 28 engagingr substantiallysimultaneously with the valve member I8 in the coupling part I8.-`

It the cap nut 881s now screwed on tothe coupling part 22, the twocoupling parts are moved towards each other, and the two valve membersI8, 28 are moved away from their seatings, since each is engaged by afixed part oi the other coupling part and the parts assume the positionsshown in Figure 3. Fluid can then flow through the coupling by way ofthe hollow stem 28, apertures 88, and cut-away portions 2I in the valvemember I8 of the coupling` part I8. As the valve member I8 in thecoupling part I8 abuts the head 28 before the valvesbegin to open, allair is excluded from between the two coupling parts, and none can betrapped and allowed to pass into the pipeline.

Fluid in the coupling part 22 can pass into the space 88 between thestem 28 and the valve member 28, but cannot escape from this space tothe exterior ofthe coupling because ot the packing ring 88 therein. 88,if under pressure, therefore exerts a thrust which assists the spring 88to retain the valve 28 in the closedposition. ,The force due to theliquid pressure acting on any exposed area to move the valve towards itsopen position will act against the closing force. When the valve isclosed the area upon which an opening force can act is substantiallynil, unless due to slight differences of angle of the valve and itsseating they are engaging at or near the outer edge only, but when thevalve begins to open due to the bringing together or the coupling parts,a part oi the external shoulder 8I is'also exposed, the extent of theexposed area depending on the position of the circumferential line alongwhich the seal takes place between the packing ring 82 on the shoulder8I and the end of the rirst coupling part I8. The parts are so made thatthis circumferential line has a smaller radius than that of the largestpart oi the space 88 between the stem 28 and the annular valve member28, so that during the connecting operation, as well as when thecoupling parts are separated, that member is urged constantly towardsits' seat by the pressure in the coupling, and cannot be moved by thepressure away from. its abutment on the coupling part I8, to allowleakage between them. The annular valve member 1e stepped mtemeuy teprovide t. shoumer u which, when the coupling parts are connected,

engages the loose ring 81 bearing on the packing A 88 and applies apositive (i. e. non-resilient) pressure to the packing ring.Alternatively, the loose ring may be of such diameter that the steppedpart of the valve member passes over it and engages directly on thesurface oi' the packing itself, the shoulder then being of Irustoconicalform. e

In the alternative form of coupling shown in Figure 4, the annular valvemember 81 is similarly arranged between a central hollow stem 88 and themain sleeve or'body 8I of the coupling part, but the valve member 81 isnot enlarged internally,.the packing ring 82 being arranged between itand the outer sleeve. The main sleeve-8l is formed with an internalannular recess 88,and the valve member is formed with a curved shoulder88, the packing ring 82 lying between the recess and the curvedshoulder, and being acted on through a washer 88 by a spring 88 in thespace 81 between thestem and the sleeve. 'Il'he spring 88 acts throughthe packing ring 82 to urge the valve towards its seat on the head 88 ofthe stem 88. Fluid from the interior of the coupling can enter the space81 behind the packing ring and assistY the spring." to hold the lvalveup against its seat.

The second coupling part of the coupling shown in Figure 4 issubstantially identical with that shown in Figure l, the body 8I beingturned in- The iluld in this-space 1 wards at its end to secure in placea seating 82 on which engages a valve member 88, .and the body 8I isformed with an external collar 88V to engage a cap nut 88 screwing on toa thread 88 on the coupling part 8l.

'I'he iluid from the interior oi the coupling enters the space 88(Figures 1 to 3) or 81 (Fig-v ure 4) by passing between the stem andthevalve member, the ilt of the surfaces of these allowing sunlcientpassage of iluld to maintain a pressure in the packing space. I!desired, ports may be formed in the wall oi the hollow stem as shown at88 in Figure 4 to provide a more tree communication, but this is notnormally essential.

By the present invention, there is provided a coupling, the parts ofwhich can be separated, left apart, and recoupled with pressuressubstantially above atmospheric pressure existing in both parts of thecoupling, without any appreciable leakage of nuid taking place, anypressure in either part of the coupling assisting the tightness of theseal.

What Iclaim is: v,

l. A pipe coupling comprising two coupling parts to be brought into endto end engagement, an annular seating member in one of said engagingends. a central valve body cooperating with said seating member, a ilxedhead forming the center of the other engaging member, a tubular supportfor said head, an annular valve member surrounding said head andslidable exare closed, whereby they may be brought into l close abutmentrelationship over their whole surfaces. and the coupling partssubsequently moved asumo? toward each other to produce an opening of thevalves.

2. A pipe coupling comprising two coupling parts designed for end to endengagement. an annular `seating member in one of the engaging ends, acentral valve body co-operating with said seating, a ilxed head formingthe center of the other engaging end, a tubular support for said head,an annular valve member surrounding said head and slidable externally onsaid tubular support, said annular valve member comprising an internallystepped sleeve with its largest internal diameter remote from the head,a sealing ring between the tubular support and the largest internaldiameter of said sleeve, an abutment for said sealing ring on thetubular support, and

means for admitting duid from the coupling to the annular space betweenthe valve member and the tubular support to apply pressure to said valvemember and urge it towards its seat, the engaging ends of the couplingparts being of substantially exact complementary form when the valvesare closed, whereby they may be brought into close abutting relationshipover their whole surfaces yand the coupling parts subsequently movedtowards each other to produce the opening of the valves.

3. A pipe coupling comprising two coupling parts designed for end to endengagement, an annular seating member in one oi' the engaging ends, acentral valve body co-operating with said seating, a fixed head formingthe center of :the other engaging end, a tubular support for said head,an annular valve member surrounding said head and slidable externally onsaid tubular support, said annular valve member comprising an internallystepped sleeve with its largest internal diameter remote from the head,a sealing ring between the tubular support and the largest internaldiameter of s/aid sleeve, an abutment for said sealing ring on thetubular support, a loose ring engaging the sealing ring on the sideopposite to the abutment, and a spring taking its abutment on the valvemember and acting to urge the loose ring against the seal, means beingprovided for admitting uid from the coupling to the annular spacebetween the valve member and the tubular support to apply pressure tosaid valve member and urge it towards its seat, the engaging ends of thecoupling parts being of substantially exact complementary form when thevalves are closed, whereby they may be brought into close abuttingrelationship over their whole surfaces and the coupling partssubsequently moved towards each other to produce the opening of thevalves.

4. A pipe coupling comprising two coupling parts designed for end to endengagement, an annular seating member in'one of the engaging ends, acentral valve body co-operating with said seating, a fixed head formingthe` center of the other engaging end, a tubular support for said head,an annular valve member surrounding said head and slidable externally onsaid tubular support, said annular valve member comprising an internallystepped sleeve with its largest internal diameter remote from the head,a sealing ring between the tubular support and the largest inv ternaldiameter of said sleeve, an abutment for 'said sealing ring on thetubular support, a loose ring engaging the sealing ring on the sideopposite to the abutment, and a spring taking its abutment on the valvemember and acting to urge the loose ring against the seal, the abutmentfor the sealing ring and the loose ring having radially outwardly`divergent faces ensaling the sealing ring, whereby the said ring isurged outwardly into engagement with the annular valve member, andmeansv for admitting fluid from the coupling to the annular spacebetween the valve member and the tubular support to apply pressure tosaid valve member and urge it towards \its seat, the engaging ends ofthe coupling parts being of substantially exact complementary form whenthe valves are closed, whereby they may be brought into close abuttingrelationship over their whole surfaces and the' coupling partssubsequently moved towards each 4other to produce the opening of thevalves.

`5. A pipe coupling comprising two coupling parts designed for end toend engagement, an annular seating member in one oi the engaging ends, acentral valve body co-operating with said seating, a xed head formingthe center oi' the other engaging end, a tubular support for said head,an annular valve member surrounding said head and slidable externally onsaid tubular support, said annular valve member comprising an internallystepped sleeve with its largest internal diameter remote from the head,a sealing ring between the tubular support and the largest internal.diameter of said sleeve, an abutment for said sealing ring onlthe'tubular support, a loose ring engaging the sealing ring on the sideopposite to the abutment, and a spring taking its abutment on the valvemember and acting to urgethe loose ring against the seal, the abutmentfor the sealing ring and the loose ring having radially outwardlydivergent faces engaging the sealing ring, whereby the said ring isurged outwardly into engagement with the annular valve member, anintermediate step in the bore of the stepped sleeve adapted to vengagethe loose ring when the coupling parts are fully coupled and applypressure to the sealing ring, and means for admitting `fluid from thecoupling to the annular space between the valve member and the tubularsupport to apply pressure to said valve member and urge it towards itsseat, the engaging ends of the coupling parts being of substantiallyexact complementary form when the valves are closed, whereby they may bebrought intoy close abutting relationship over their whole surfaces andthe coupling parts subsequently moved towards Ieacln other to producethe opening of the valves.

6. A pipe coupling comprising two coupling parts designed for end to endengagement, an annular seating member in one of the engaging ends, acentral valve body co-operating with said seating, a fixed head formingthe center of the other engaging end, a tubular support for said head,an annular valve member surrounding said head and slidable externally onsaid tubular`\sup port, said annular valve member bounding at one end anannular space around said tubular support, an outer sleeve concentricwith the tubular support and in which said tubular support is rigidlyattached, an internal circumferential groove insaid outer sleeve, ashoulder in said armnular valve member, a sealing ring lying in saidcircumferential groove and engaging said shoulder, and means foradmitting fluid from the coupling to said annular space to applypressure to said valve member and urge it towards its seat, the engagingends of the coupling parts being of substantially exact complementaryform when the valves are closed, whereby they may be brought into closeabutting relationship over their whole surfaces and the coupling partssubseopening oi' the valves.

f7. `A pipe coupling comprising two coupling parts designed for end` toendengagement, an annular seating member in one oi' the engaging ends, acentral valvebody comperating with said seating, a ilxed head formingthe center oi the other engaging end, a tubular support tor said head,an annular valve member surrounding said head and slida'ble externallyon said tubular support, said annular valve member bounding at one endan annular space around said tubular support. an outer sleeve concentricwith the tubular support and in which said tubular support is rigidlyattached. an internal circumferential groove in said outer sleeve, ashoulder in quently moved towards each other to produce the i v overtheir whole surfaces and the coupling parts subsequently moved towardseach other to producetheopeningotthev'alves. y

- REGINALDJOHN FISHER.

